JP2016193485A - System, selection method of fine adjustment speed, and non-temporary computer-readable medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system and a method for selecting fine adjustment speed for reducing chatter of a machine, and to provide a computer-readable medium.SOLUTION: A system includes a circuit constituted so as to judge machine speed determined beforehand. The circuit discriminates a stable lobe based on the machine speed determined beforehand, and selects fine adjustment speed in a first group from a range of the machine speed corresponding to the discriminated stable lobe. Further, the circuit operates the machine by one or more of each fine adjustment speed in the first group.SELECTED DRAWING: Figure 3A

Description

  The present application relates to a system for reducing machine tool chatter, a method for selecting a fine tuning speed, a computer readable medium, and an interface.

  For example, as described in US Pat. No. 5,170,358, which is hereby incorporated by reference in its entirety, chatter or instability in machining operations such as turning, drilling, and milling is It is a common problem. Vibration is mainly classified into free vibration, forced vibration, and self-excited vibration. Chatter is a type of self-excited vibration that is often observed during machining operations (or processes). Chatter can also result from forced vibration under certain operating conditions.

US Pat. No. 5,170,358

  Chatter is unwanted vibration observed during machining operations. It may be caused by an undesirable vibration feedback loop through the machine tool, workpiece, and machine. When generated, the vibration from the feedback loop can often be damped by changing the tool rotation speed (changing the drive vibration frequency) with respect to the chatter frequency (response frequency). Embodiments of the present disclosure are directed to facilitating reduced chatter.

  According to one embodiment of the present disclosure, a system is provided. The system includes a circuit that is configured to determine a predetermined speed of the machine. The circuit identifies a stability lobe based on a predetermined speed of the machine and selects a first set of fine tuning speeds from a range of machine speeds corresponding to the identified stability lobe. The circuit also operates the machine at one or more of the first set of fine tuning speeds.

  According to one embodiment of the present disclosure, a method for selecting a fine tuning speed to reduce machine chatter is provided. The fine tuning speed selection method includes the step of determining the predetermined speed of the machine by the circuitry of the system. The circuit identifies the stability lobe based on the machine's predetermined speed. The circuit selects a first set of fine tuning speeds from a range of machine speeds corresponding to the identified stability lobes. The fine tuning speed selection method also includes the step of operating the machine at one or more of the first set of fine tuning speeds.

  In addition, according to an embodiment of the present disclosure, a non-temporary program that, when executed by a computer, stores a program that causes the computer to perform a method of selecting a fine adjustment speed for reducing machine chatter as described above. A computer readable medium is provided.

  The general description of the foregoing exemplary implementation and the following detailed description thereof are merely exemplary aspects of the teachings of this disclosure and are not limiting.

FIG. 2 illustrates an exemplary machine tool that can generate chatter, according to one embodiment. FIG. 3 illustrates an exemplary chatter application interface according to one embodiment. FIG. 6 shows a flowchart for the creation of an exemplary chatter application interface according to one embodiment. FIG. 6 is a flowchart of a fine adjustment speed method according to an embodiment. FIG. 6 is a flowchart of a fine adjustment speed method according to an embodiment. It is a figure which shows the fine adjustment speed screen according to one Embodiment. It is a figure which shows the fine adjustment speed screen according to one Embodiment. FIG. 4 illustrates an exemplary stability lobe diagram according to one embodiment. FIG. 4 illustrates an exemplary stability lobe diagram according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using an arithmetic progression method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a first set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. FIG. 6 illustrates exemplary choices for a second set of fine-tuning speeds calculated using a harmonic sequence method and included in a speed bar, according to one embodiment. It is a block diagram which shows an example of the hardware constitutions of a computer. FIG. 2 illustrates a system for implementing a fine tune speed interface according to one embodiment.

  In the drawings, like reference characters designate like or corresponding parts throughout the several views. The drawings are generally drawn to scale unless otherwise indicated or unless schematic structures or flowcharts are shown.

  In addition, the terms “about”, “approximate”, “subordinate”, and similar terms are generally, in some embodiments, identified values within a 20%, 10%, or preferably 5% margin, and Refers to a range that includes any value between.

  The terms “speed”, “spindle speed”, “selected speed” and similar terms refer to “tool speed” or “workpiece speed” at speeds per minute (rpm) unless otherwise stated. ". However, it is understood that embodiments of the present disclosure are not so limited and other units of speed may be utilized.

  Vibrations that occur during machining operations can be monitored using, for example, one or more sensors. One or more sensors may be configured to measure vibration directly or indirectly during a machining operation. Sensor data received from one or more sensors is used to calculate a rotational speed that reduces chatter, for example using one or more methods to eliminate the phase difference between driving and driven vibrations. Is possible. Based on the calculated speed, chatter can be eliminated or reduced by changing the rotational speed manually or automatically.

  In some embodiments, the machine is controlled by one or more computer numerical control (CNC) machines. A CNC machine typically implements an NC program written in a programming language such as G-code, which controls parameters related to the tool or workpiece such as speed, machining coordinates, tool type. That is, the NC program includes machining instructions such as how to move the tool or workpiece and at what speed to rotate the tool or workpiece. The rotational speed may also be controlled by an operator (or user) via one or more user interfaces provided by one or more CNC machines or another computer. The user interface is configured to display one or a combination of chatter data and the result of a calculation that reduces chatter to guide the user to activate one or more desired rotational speeds. May be. However, in such a configuration, speed data, chatter data, and activation methods may be greatly separated.

  In order to deal with this problem, chatter history data can be incorporated into the corresponding speed information and provided to the operator. When trying multiple rotational speeds to find the optimal rotational speed, a history of tried speeds (or previously selected speeds) and the corresponding chatter size can be saved and displayed to the operator. Such data may be displayed in the form of a table or a graph. However, due to screen size limitations, it may not be practical to show the entire range of chatter data simultaneously.

  In order to more effectively and economically reduce chatter during one or more machining operations, there is a need for an interface and / or method that facilitates repeated selection of operating speeds. For fine-tuning speed resolution based on stable lobe theory, stable lobe theory alone cannot find the best speed, possibly due to multiple chatter frequencies or inherent inaccuracies of the method. However, over a given speed range, it is expected that there will be non-random periodicity for stable versus unstable speed, and this fact can be used to determine the most efficient speed resolution to use for fine tuning It is.

  FIG. 1 illustrates an exemplary machine 100 according to one embodiment of the present disclosure. The machine 100 includes a spindle housing 101, a cutting tool 102 (eg, a cutting, turning, drilling or milling tool), a workpiece 103, and one or more sensors (eg, vibration sensors 104 and 105). The spindle housing 101 includes a mechanism for holding the cutting tool 102 in a desired position. The spindle housing 101 also includes a motor (not shown) that rotates the cutting tool 102 at different speeds. The cutting tool 102 rotates at a selected speed while in contact with the workpiece 103, for example to shape the workpiece 103 by removing material. The movement of the cutting tool 102 and the workpiece 103 is controlled, for example, through a computer 1000 as shown in FIG. 10 and / or operator action. However, as mentioned above, in another embodiment, for example, a lathe (turning machine) may be used to rotate the workpiece 103 while the cutting tool 102 remains fixed.

  The vibration sensors 104 and 105 are arranged at different locations on the spindle housing 101. In some embodiments, the sensor may be located on the workpiece, or the vibration is measured indirectly, for example using a microphone to measure sound waves caused by vibration on the tool or workpiece. May be. The vibration sensor measures vibrations that occur during the machining process and provides vibration data to a control computer (eg, computer 1000) where the vibration data is processed.

  The processed data may be displayed on a user interface through which an operator interacts to operate the machine 100. For example, vibration data such as vibration magnitude data may be used to calculate one or more optimal chatter reduction parameters such as the speed displayed on the user interface. As the speed changes, the magnitude of the vibration changes and new data is provided at the interface. The speed at which significantly smaller vibration magnitudes are observed can be identified using the interface and can be a good evaluation method for identifying the optimal chatter level speed setting. The one or more parameters act as an operator's guide, and the operator can then make an appropriate selection on the user interface to reduce the chatter observed during one or more machining operations.

  FIG. 2A is an exemplary diagram of a chatter application interface (CAI). The CAI 200 includes one or more elements. For example, CAI 200 includes four elements, such as a chatter gauge element 201, a vibration display element 225, a speed bar 215, and a history bar 220. Each element displays information regarding control of chatter level during machining operations. CAI 200 is further described in US application Ser. No. 14 / 526,111 filed Oct. 28, 2014, which is hereby incorporated by reference in its entirety.

  The chatter gauge element 201 is displayed in this embodiment as a circular dial 203, which is a fixed gauge mark 211, an adjustable chatter threshold mark 205, a current chatter level numeric display 207, and a current chatter level indicator. 209. A current chatter level numeric display and a current chatter level indicator 209 indicate real-time chatter that occurs during a machining operation.

  Speed bar 215 displays one or more selectable candidate speeds for the machining operation. Candidate speeds in the speed bar 215 are generated based on the calculation of one or more chatter-free spindle speeds that will potentially reduce existing chatter observed during machining operations. An exemplary determination method is described below. However, different methods can be used to perform one or more calculations, and the present embodiment is not limited to any particular calculation method. Various chatter reduction methods include stability lobe methods, time domain numerical modeling methods, analytical approaches to model tools or work dynamics, and the like.

  FIG. 2B is a flowchart of a method for generating a CAI 200 according to an embodiment of the present disclosure. As soon as the machine 100 is switched on or the initialization process is started otherwise, the CAI generation process begins. The initialization step 201c initializes one or more machining-related parameters such as the total number of tool blades, minimum rotation speed, maximum rotation speed, chatter threshold, and / or clears the speed and chatter vibration database. It involves doing. In step 202c, an initial machining speed (or initial rotational speed setting) is selected (either automatically or by an operator) and the machining process begins. Data collection step 203c involves reading or collecting data during the machining process. For example, vibration sensor data is read in step 204c, or the current spindle speed is read in step 206c. Once sensor data is collected, it can be converted to a different form. For example, in step 205c, the vibration sensor data is converted to frequency domain data using Fast Fourier Transformation (FFT).

  Following the data collection step 203c is a data handling step 207c. In the data handling step 207c, the sensor data is processed according to the design specifications (for example, chatter calculation). For example, vibration data from multiple sensors is processed in some way (eg, averaged and weighted). Processing the vibration data includes generating (eg, by determining or measuring) chatter level values and chatter frequency values based on the vibration data. In one embodiment, the chatter level value corresponds to the maximum chatter level detected during use of the tool at that rate, and the chatter frequency is the maximum vibration measured during the occurrence of the maximum chatter level. Is the frequency. Step 207c may also involve vibration filtering data associated with chatter and data filtering algorithms that may be used to eliminate noise in the sensor data.

  After the data handling step 207c, steps 208c and 210c are executed in parallel. Step 208c is a state check for evaluating whether or not chatter vibration is larger than the chatter threshold set in step 201c. If step 208c evaluates to false (no), the process returns to step 203c. If step 208c evaluates to true (yes), the process proceeds to step 209c. In one embodiment, the process proceeds to step 209c regardless of the condition check at 208c.

  In step 209c, a spindle speed calculation module without chatter (or a spindle speed calculation module with reduced chatter) is used to determine one or more candidate speeds that are predicted to reduce or eliminate chatter. calculate. In one embodiment, the one or more candidate speeds are speeds at which the chatter level is predicted to be lower than one or more predetermined chatter thresholds. The chatterless spindle speed calculation module calculates one or more candidate spindle speeds (or candidate rotational speed settings) provided in the speed bar of the CAI 200.

  In one embodiment, the calculation of chatter-free spindle speed is based on a stability lobe determination method (an exemplary stability lobe diagram is shown in FIG. 5). However, it should be noted that a variety of different methods can be used to perform the calculations, and the present embodiment is not limited to any particular calculation method. Various chatter reduction methods include stable lobe methods, time domain numerical modeling methods, analytical approaches to model tool dynamics, and the like.

  An exemplary approach for calculation of spindle speed without chatter involves the use of Equation 1.

  Where n stable speed is the stable (no chatter) speed per revolution (rpm) per lobe, f chatter is the chatter frequency in hertz (Hz), N flutes is the total number of tool blades , I is the number of lobes -1, 2, 3, etc.

  Equation 1 shows that each lobe number is associated with a stable speed. The stable speed of the lobe corresponds to a peak in a stable lobe diagram as shown in FIG. 5, for example. As the number of lobes decreases, the stabilization rate increases.

  The lobe number corresponds to an integer derived from the ratio of the base speed to a given machine speed (eg, tool rotation speed or workpiece rotation speed). Depending on the embodiment, a given machine speed may refer to a candidate speed or a current speed. For maximum speed, the lobe number is its minimum. For the lowest speed, the number of lobes is its maximum. Equation 2 of the number of lobes is as follows.

  The base speed is calculated using Equation 3 as follows:

  In step 210c, the speed and chatter vibration data from step 207c is stored in one or more databases. Velocity and chatter vibration data can be extracted on demand in other steps such as step 211c. In some embodiments, the one or more databases are also configured to store velocity and chatter vibration data from one or more different past machining operations, eg, for different workpieces but the same cutting tool. . All or part of the speed and chatter vibration data from one or more different past machining operations may be stored in one or more databases. A portion of the speed and chatter vibration data may be selected based on one or more speeds associated with the lowest chatter vibration level.

  In step 211c, a speed bar display is generated. The speed bar is calculated in step 209c with one or a combination of previously selected speeds (eg, including initial speed and / or one or more tried speeds) from the speed and chatter vibration database. The displayed candidate speeds are displayed. An exemplary speed bar 215 display is shown in FIG. 2A. The candidate speed options displayed in the speed bar may or may not be selected.

  In step 212c, a determination is made as to whether a new speed has been selected from the candidate speeds displayed in the speed bar. If no new speed has been selected, the process returns to step 203c. If a new speed has been selected, step 213c is executed and a new speed is activated. For manual speed changes, a new speed from the speed bar display may be selected by the operator using the CAI 200. However, according to certain embodiments, the speed change may be automatically selected.

  In step 215c, a determination is made as to whether fine adjustment should be performed. If fine adjustment is to be performed, a fine adjustment speed generation process at step 300 is performed. If no fine adjustment is to be made, the process returns to data collection step 203c. The fine tuning process may be triggered automatically or manually. Automatic fine tuning decisions can be made based on the difference between the current chatter and the chatter threshold. For example, if the difference is greater than 10%, the fine adjustment speed may automatically pop up on the speed bar and / or an automatic fine adjustment process may be performed. In the manual setting, a fine adjustment button or a zoom button may be provided. When a fine adjustment button or zoom button is activated by an operator, a fine adjustment speed may pop up on the speed bar and / or an automatic fine adjustment process may be performed. Alternatively, the fine-tuning process may be triggered in any other way, such as when the operator double taps the current speed or other speed, or when the selection is repeated in other ways. Good.

  At step 300, one or more fine tuning speeds are generated around a predetermined rotational speed and displayed in a speed bar, depending on the embodiment. The predetermined rotational speed may be an initial speed set in the NC program or by an operator. In one embodiment, the predetermined rotational speed is selected from one of the candidate speeds calculated using a stable speed method, for example using Equation 1 below. FIG. 3A is primarily described using the current speed as an example. However, the method described in FIG. 3A is equally applicable to the other predetermined rotational speeds described above. One embodiment of the fine tuning process is shown in FIGS. 3A and 3B and is further described below. After fine-tuning has been made, the process optionally continues to data collection step 203c.

  History bar 220 displays historical data associated with the previously selected speed and the currently selected speed along the speed axis. Historical data is extracted from the populated speed and chatter database using step 210c.

  In one embodiment, the original speed bar is modified to further display the fine tune speed to further reduce chatter. In another embodiment, automatic fine tuning is performed with or without modification of the original speed bar display. 3A and 3B illustrate an exemplary method for fine tuning speed control of chatter level during one or more machining operations. This method is iterative in nature, producing fine-tuning speeds in multiple increments until a minimum (or otherwise acceptable) chatter level is achieved. As mentioned above, the fine adjustment speed may or may not be displayed on the speed bar. In some embodiments, the fine tune speed is displayed separately from the speed bar.

  At step 305, the current speed or another predetermined machine speed is identified from the speed bar generated by the process shown in FIG. 2B. In one embodiment, the current speed is stored in the machine controller to control the spindle speed as needed. As described above, the speed bar not only displays the candidate speed to reduce chatter, but also displays one or a combination of the current speed, the initial speed, and the previously selected speed. To do.

  At step 310, lobes corresponding to the current speed or another predetermined machine speed are identified. For example, the number of lobes can be determined from the data used to generate the velocity bar or can be calculated using Equation 2 as described above. In general, the number of lobes indicates a particular stability lobe in a stability lobe diagram for a particular machine / tool / machining state combination, and this stability lobe is further associated with a range of speeds. The stability lobe diagram can be predetermined for a particular machine state and stored in a database.

  In certain embodiments, a stability lobe diagram may be generated based on machining data collected during a machining operation, or an existing stability lobe diagram may be updated. Stable lobe diagrams are derived from historical chatter data collected during machining processes, computer simulations, and combinations thereof, by including analytical and experimental approaches (eg, using Equations 1-3). It can be generated in several ways. Also, in some embodiments, multiple stability lobe diagrams can be generated as the dynamic state changes during the machining process and different chatter frequencies are observed for the same speed. These stability lobe diagrams are combined using simple averaging, weighted averaging, or other statistical techniques (eg, when updating), and then to calculate one or more optimal velocities Can be used.

  To calculate the optimal (or otherwise acceptable) speed in this embodiment, a stability lobe corresponding to the current speed (or any other selected speed) is determined at step 315. . The stability lobe may be identified automatically or manually by the user via user input. One or a combination of different methods may be utilized to calculate the fine-tuning rate, including the use of an arithmetic or harmonic sequence, described in more detail below. For example, one method may be used to calculate a first set of fine tuning speeds, and the same or a different method may be used to calculate a second set of fine tuning speeds. In some embodiments, one or more additional sets of fine-tuning rates may be calculated. In some embodiments, the fine tuning speed may span multiple lobes (eg, two adjacent lobes).

  In one embodiment, when using the arithmetic progression method, the spacing between the fine-tuning speeds in each stabilization lobe is calculated using the determined stability lobe width in which the fine-tuning speeds are to be calculated. The A set of fine adjustment speeds is selected such that the fine adjustment speeds are separated based on the calculated intervals. In another embodiment, when using the arithmetic sequence method, the range of machine speed is specified by the user instead of based on the width of the stability lobe, and the first set of fine adjustments according to the specified range of split points. A speed is selected from a range of speeds. In another embodiment, when using the harmonic sequence method, a set of fine tuning speeds is selected using the base speed and the determined number of lobe lobes for which the fine tuning speed is to be calculated. The Examples of the arithmetic and harmonic sequence methods are described below with respect to FIGS. 6-7 and FIGS. 8-9, respectively.

  In one embodiment, when using the arithmetic progression method, the first set of fine-tuning speeds may be predetermined starting from the calculation of the base speed using Equations 1 and 3. Also, a stable speed can be calculated for each lobe number, which can then be used to calculate a speed range for each lobe number. A first interval between speeds is determined by dividing the determined speed range by a first predetermined number (eg, 10). Next, a first set of fine tuning speeds is selected from a range of machine speeds centered on the current speed.

  In one embodiment, each of the first set of fine tuning speeds is separated by a first interval or otherwise based on the first interval. In one embodiment, the fine adjustment speeds in the first set of fine adjustment speeds are equally spaced. The ten speeds act as a first set of fine-tuning speeds and, depending on the embodiment, are displayed on the speed bar with the current speed at step 320.

  Usually, the lobe width separates the stable speeds. However, if there are multiple chatter frequencies, the stable velocity region may be affected by other frequency lobes. Dynamic machine characteristics may also affect the accuracy of stable speed prediction.

  At step 325, a determination is made as to which of the first set of fine-tuning speeds has the lowest chatter level or is otherwise acceptable. In one embodiment, each of the first set of fine tuning speeds is scanned to automatically determine which of the first set of fine tuning speeds corresponds to the lowest chatter value. For example, the machine is operated at each of the first set of fine tuning speeds, the chatter level is measured at each operating speed, and the lowest chatter value is selected from the measured chatter levels. In another embodiment, the machine is operated only with a portion of the first set of fine-tuning speeds, for example, until a speed having a chatter level below a predetermined threshold is identified. In another embodiment, the operator selects one or more different fine-tuning speeds displayed in the speed bar until a speed with minimized (or otherwise acceptable) chatter is selected. . For example, the chatter level for each of one or more selected different fine-tuning speeds is measured and displayed to the operator with a speed bar. The selected one of the first set of fine tuning speeds becomes the current speed.

  Step 325 is a sub-process shown in FIG. 3B and described below. Also, at step 330, a stable lobe speed range corresponding to the selected fine adjustment speed (selected at step 325) is generated by a second predetermined number to generate a second set of fine adjustment speeds. It is divided into (for example, 40) parts (speed). For example, when using an arithmetic sequence, the second interval is determined by dividing the determined lobe width by a second predetermined number. Next, a second set of fine tuning speeds is selected from the range of machine speeds. In one embodiment, each of the second set of fine tuning speeds is separated by a second interval or otherwise based on the second interval. Also, in one embodiment, the second set of fine tuning speeds are equally spaced.

  As noted above, in some embodiments, the second set of fine tuning speeds is selected from only a portion of the speed range of the stability lobe. For example, the second set of fine-tuning speeds may be current between two of the first set of fine-tuning speeds, eg, two of the first set of fine-tuning speeds adjacent to the current speed. It is selected from a speed range of a stability lobe located such as between the speed and one of the first set of fine tuning speeds adjacent to the current speed.

  In some embodiments, the first predetermined number is less than the second predetermined number. The larger spacing associated with the first predetermined number, for example, allows efficient scanning of one full lobe width. Once a minimum value or other acceptable value is found, a smaller interval associated with the second predetermined number may be used to identify. Thus, a finer speed resolution can be obtained to identify the speed that will further minimize the chatter level. However, in other embodiments, the first predetermined number may be greater than or equal to the second predetermined number.

  At step 335, the second set of fine-tuning speeds is optionally displayed on the speed bar along with the current speed. For example, when the optimum one of the second set of fine adjustment speeds is automatically determined, the second set of fine adjustment speeds may not be displayed. However, in another embodiment of manual selection or automatic determination, the second set of fine adjustment speeds is displayed to the user.

  At step 340, a determination is made as to which of the second set of fine tuning speeds has the lowest chatter level or is otherwise acceptable. In one embodiment, each of the second set of fine tuning speeds is scanned to automatically determine which of the second set of fine tuning speeds corresponds to the lowest chatter value. For example, the machine is operated at each of the second set of fine tuning speeds, the chatter level is measured at each operating speed, and the lowest chatter value is selected from the measured chatter levels. In another embodiment, the machine is operated only at a portion of the second set of fine-tuning speeds, for example, until a speed having a chatter level below a predetermined threshold is identified. In another embodiment, until a speed with minimized (or otherwise acceptable) chatter is selected, the operator may, for example, 1 from a second set of fine-tuning speeds displayed in the speed bar. Select one or more different fine-tuning speeds. For example, the chatter level for each of one or more selected different fine-tuning speeds is measured and displayed to the operator with a speed bar. The selected one of the second set of fine tuning speeds becomes the current speed.

  As described above, dividing the velocity range associated with the current velocity stability lobe and / or adjacent lobes into a first predetermined number (eg, 10) can be done in different ways. In one embodiment, 10 speeds may be obtained by dividing the speed range into 10 equal parts (ie, using an arithmetic sequence). For example, consider that the initial condition is that the cutting tool has three cutting edges (number of blades), the minimum allowable speed is 10,000 rpm, and the maximum allowable speed is 20000 rpm. The machining process begins and the measured chatter frequency is 1800 Hz.

Based on the initial conditions, the base speed can be calculated using Equation 3 as follows:
Base speed = chatter frequency * 60 / cutting edge = 1800 * 60/3 = 36000 rpm
Also, the stable lobe speed can be calculated using Equation 1 as follows:
Lobe 1 speed = base speed / 1 = 36000 rpm
Lobe 2 speed = base speed / 2 = 18000 rpm
Lobe 3 speed = base speed / 3 = 12000 rpm
Lobe 4 speed = base speed / 4 = 9000 rpm
The speed range of lobe N is from the speed of lobe N + 1 to the speed of lobe N. For example, the speed range of lobe 3 is from the speed of lobe 4 to the speed of lobe 3, numerically from 9000 rpm to 12000 rpm. In that case, the allowable tool speed in the example ranges from lobe 1 to lobe 4 according to the minimum speed criterion and the maximum speed criterion. Note that each lobe has a different width, and the width increases as the number of lobes decreases. Tables 1 and 2 below show exemplary lobe velocities calculated using Equation 1. Table 2 includes more stable speeds for the same chatter state as Table 1. As the tool speed limit is relaxed, additional speed becomes available.

  Table 1: Calculated speed without chatter

  Table 2: Additional calculated, chatter-free speed

  Based on the lobe speed, a fine-tuning interval within one lobe width can be calculated by dividing the speed range corresponding to that lobe width by a first predetermined number (eg, 10). For example, the spacing for lobe 3 is (lobe 3 speed−lobe 4 speed) / 10 = (12000−9000) / 10 = 300 rpm. Similarly, the spacing for lobe 2 is (18000-12000) / 10 = 600 rpm, and the spacing for lobe 1 is (36000-18000) / 10 = 1800 rpm. The spacing for each lobe is further used to calculate the fine tuning rate. For example, if the entire speed range of the tool is 10000-20000 rpm, the fine-tuning speeds that fall within the range of the minimum speed reference and the maximum speed reference in one example are 10200, 10500, 10800, 11100, 11400, 11700, 12000, 12600, 13200. 13800, 14400, 15000, 15600, 16200, 16800, 17400, 18000, and 19800. The fine-tuning speed calculation for the sequence of differences between lobe 4 and lobe 3 that also included two cross-border speeds is presented in Table 3.

  Table 3: Calculation of sample fine-tuning speed using an arithmetic progression

  Also, if desired, the minimum speed of 10000 rpm and the maximum speed of 20000 rpm do not correspond to the calculated fine adjustment speed in this example, but may be added to the first set of fine adjustment speeds. The advantage of the arithmetic sequence method is that since the spacing is based on the lobe width, the step size of the fine-tuning speed increases as the lobe width increases, making good speed searches more efficient. . On the other hand, the drawback may be that there is a large jump at the lobe boundary speed. For example, at 18000 rpm, the speed increment changes from 600 rpm to 1800 rpm.

  In another embodiment, a harmonic sequence method may be used to calculate the fine tuning rate. The harmonic sequence method, according to one embodiment of the present disclosure, enjoys the advantages of the arithmetic sequence method, but eliminates some of its disadvantages. The harmonic sequence method is defined as the reciprocal sequence of the arithmetic sequence. The starting arithmetic sequence is N / base speed, (N−0.1) / base speed, (N−0.2) / base speed, (N−0.3) / base speed, and the like. Next, the reciprocal of each element individually becomes the fine adjustment speed. In the harmonic sequence method, not only the lobe speed (eg, corresponding to the candidate speed), but all fine-tuning speeds can be calculated using the base speed. For example, between lobe 4 and lobe 3, the base speed is set to 4, 3.9, 3.8, 3.7, 3.6, 3.5, 3.4, 3, 3 to obtain a fine adjustment speed. Divide by 3, 3.2, 3.1, 3.0. This will cause the 10 fine tuning speeds to be spaced apart in the harmonic sequence across the stability lobe and will match the harmonic characteristics of the actual stability lobe. As the spindle speed increases, the fine-tuning speed increments become larger and there will be no jumps at the lobe boundaries. Examples of actual speed calculation results for the entire speed range of the tool are 10,000, 10286, 10588, 10909, 11250, 11613, 12000, 12414, 12857, 13333, 13846, 14400, 15000, 15622, 16364, 17143, 18000, 18947, 20000. In some cases, any speed corresponding to a non-integer value may be rounded to the nearest integer value. The fine-tuning speed calculation for the harmonic sequence between lobe 4 and lobe 3 that also included two cross-border speeds is presented in Table 4 below.

  Table 4: Calculation of sample fine-tuning speed using harmonic sequence

  In another embodiment, a statistical distribution such as a normal distribution or a Gaussian distribution may be fitted around the current speed, and 10 speeds from the speed range based on standard deviation (shown as sigma) or variation calculations. It may be selected. For example, a speed within 6 sigma distance around the current speed can be selected (eg, the endpoint can be defined by (current speed−3 * sigma) and (current speed + 3 * sigma)). In this case, it is not necessary to calculate the end point of the stable lobe. Variations in speed between current speed lobes or adjacent lobes can be predetermined from historical data.

  In another embodiment, a weighted speed method may be implemented, where a higher weight is assigned to a speed that is closer to the current speed and a lower weight is assigned to a speed that is further from the current speed. . In one embodiment, a higher weight may be given to a speed that is close to the stability speed. The first or second set of fine adjustment speeds can be selected based on weighting. The pre-weighted speed around the current speed itself can be calculated based on one or a combination of the arithmetic sequence method, harmonic sequence method, or other statistical methods as described above. is there. In another embodiment, historical data may be used with any of the speed division methods described above. For example, if any of the ten speeds is close to the tried speed (eg, less than 5%), the speed may be omitted and replaced with the tried speed. According to a similar approach, a second set of speeds can be determined by dividing the speed range into a second predetermined number (eg, 40).

  In one embodiment, steps 325 or 340 may cause the operator or automated fine-tuning process to select and activate a new speed until a speed with minimal (or otherwise acceptable) chatter is determined. It is a sub-process and is shown in more detail in FIG. 3B. The desired range of chatter levels can be set from zero to the chatter threshold level or from zero to the chatter level corresponding to the critical cut depth (line 520 in FIG. 5A). If at step 345 it is determined that the operator or automated fine tuning process has selected a new speed, then at step 350 the new speed is activated.

  Speed activation by the operator may be realized in various ways. For example, in one embodiment of the present disclosure, the operator can drag the button upward and release it in that position. Different speed activation methods can be employed as well. For example, the desired speed may be activated by tapping multiple times, holding the button and dragging in one or more predetermined directions (eg, sideways). For analog implementations, a switch or rotary dial may be provided to activate the desired speed. The interface may also be a combination of digital and analog parts.

  Once the selected fine tuning speed is activated, in step 355, the chatter level corresponding to the current speed is measured. At step 360, the current speed and measured chatter level are stored in the database. The stored data is then used at step 365 to determine the speed having the minimum or otherwise acceptable chatter level. If it is determined at step 370 that the desired chatter level has not been achieved, a new speed is selected at step 345 and the process continues. If the desired chatter level is achieved at step 370, sub-process 325 (or 340) ends and continues to the next step in the process shown in FIG. 3A. If sub-process 325 is invoked after step 320, the next step in the process shown in FIG. Or, if sub-process 340 is invoked after step 335, the next step may be terminated.

  In one embodiment, optional step 370 involves providing the user with a visual or other indication as to whether the desired chatter level has been achieved. The display may be triggered based on historical data. For example, the current chatter level may be compared to historical chatter data for tried speeds that are within 5% of the current speed, and the difference between the current chatter and the historical chatter is less than a percentage (eg, 10%). The message “Acceptable chatter level has been achieved” may be displayed. However, if the historical data indicates that a lower chatter level can be achieved, the interface may prompt the user to select a new speed. In another embodiment, if the speed is not further selected, it is determined that the desired chatter level has been achieved. Alternatively, a minimum achievable chatter threshold may be set, which will trigger an indicator to stop the fine tuning process. The minimum achievable chatter threshold may be determined based on historical data collected during different machining processes performed during the machine life cycle.

  Depending on the embodiment, step 370 may be performed automatically or based on one or more user inputs. For example, it is determined whether a desired chatter level has been achieved based on a comparison with a predetermined threshold. In some embodiments, the determination at step 370 is made only after a predetermined number of sets of fine tuning speeds have been selected. For example, after the chatter level is measured for some or all of the predetermined fine tuning speeds of the first or second set of fine tuning speeds, the speed with the minimum chatter level is determined. .

  One or more of the steps in sub-process 325 may be automated. In an automated process, no operator intervention may be required. The fine-tuning speed may be selected automatically by the computer performing process 325 based on logic that involves comparing the chatter level to a threshold or to the tool's past chatter level history. Good. The comparison may be based on an error function that calculates the difference between the current chatter level and a past or set chatter level.

  4A and 4B show fine adjustment speed screens 215A, 215B according to one embodiment. Note that the legend shown in FIG. 4A also applies to FIG. 4B. Fine adjustment speed buttons are embedded in the fine adjustment speed screens 215A and 215B, and when a different speed is selected and added in response to a user request or the like, it is automatically added around the current speed. . Referring to FIG. 4A, the fine adjustment speed is displayed as an elliptical button together with the current speed 405a of the lobe number 10, 1241 rpm, and chatter level 1.5.

  In one embodiment, one or more of the fine tune speeds generated by the process shown in FIG. 3A or included in the number of stable lobes to be fine tuned include an initial speed or a previously tried speed. May be. For example, in FIG. 4A, a speed 410a representing 1200 rpm is an initial speed and has 10 lobes and a chatter level of 1.8. Therefore, the speed 410a is displayed with an initial speed format, that is, a rectangular button having a point at the upper left corner of the rectangle. There are no other tried speeds within the displayed fine adjustment speed range. Note that the current speed 405a should be considered a tried speed. Because it has been tried as a stable speed, it has tried lobe information on the measured lobe number and chatter level.

  Referring to FIG. 4B, the fine tuning speeds are arranged in ascending order around the current speed 405b of lobe number 11, 1441 rpm, chatter level 1.5. There are no tried speeds other than the current speed within the range of the displayed fine adjustment speed. Also, other candidate speeds are pushed out of the speed bar due to display space limitations.

  In addition, an implementation example of the fine adjustment speed is possible. Fine tuning speed may be achieved using different shapes and configurations. The fine adjustment speed button is distinguished from the candidate speed represented by the initial speed bar button (for example, the stable speed or the predicted speed of the minimum chatter). For example, a triangular button or a hexagonal button may be used to identify the fine tuning speed. Depending on the embodiment, the shape used for a fine-tuning speed will change or not change when that particular fine-tuning speed is selected. In one embodiment, the shape used for the fine-tuning speed changes to a tried speed, a candidate speed shape (eg, a square), or a different shape after the fine-tuning speed is selected. In another embodiment, the shape used for fine tuning speed does not change after it is selected. In this case, the selected (or tried) fine-tuning speed is optional, with additional information (eg, measured chatter level, number of stable lobes) or color coding in or around the shape associated with the fine-tuning speed May be distinguished from fine-tuning speeds that have not been selected (or have not yet been tried). For example, the fine tuning speed is initially displayed as a white ellipse, which may be filled with a color when selected. According to one embodiment, the color is based on the measured chatter level. In another embodiment, the color is a predetermined color. Also, in certain embodiments, fine tuning speed indications for different fine tuning speed sets may be distinguished by shape, color, and / or other identification or additional information. For example, the first set of fine adjustment speeds may be displayed using an ellipse, while the second set of fine adjustment speeds may be displayed using a circle.

  FIG. 5A illustrates an exemplary stability lobe diagram on which a fine-tuning speed determination process is based, according to an embodiment. FIG. 5B illustrates speeds that exceed minimum and maximum speed limits (eg, 10000 and 20000) to allow fine-tuning speed calculations for different machining operations that may have lower or higher machining speed requirements. FIG. 6 is an expanded stability lobe diagram with a speed ranging from 5000 to 40000 including In one embodiment, the extended speed range is enabled by relaxing the tool speed limit. Referring to FIG. 5A, the peak of the stability curve represents the maximum value of the cutting depth without chatter at the main shaft rotation speed, which is called the stable speed. The area between the peaks is called the stability lobe. For example, stability lobes 1, 2, 3, and 4 are represented by 501, 502, 503, and 504, respectively. Peaks 502a, 503a, and 504a represent the stable speeds associated with lobe 2, lobe 3, and lobe 4, respectively. Line 520 is the critical depth of cut below which there is very little or no chatter for any given speed. Typically, a speed with minimum chatter and maximum depth of cut is desired.

  As can be seen, the width of the stability lobe changes and increases with increasing spindle speed. Lobes sequentially populate from large to small lobe numbers over a given speed range from low to high. The harmonic nature of the chatter size is repeated over the velocity range, with the minimum chatter peak at each lobe boundary represented and marked by peaks 502a, 503a and 504a. As the lobe velocity range increases, the width of each lobe increases. According to an embodiment of the present disclosure, when considering the harmonic nature of chatter itself, the fine tuning method takes into account the increasing width so that each fine tuning speed step is an equal step. When referring to a single velocity, the boundary between stable lobes is referred to using a larger number of lobes. For example, the fifth to fourth lobe boundaries are referred to as “lobe 5” (as opposed to “lobe 4”).

  6A-6D illustrate an example interface display when a different speed is selected, eg, from a first set of fine-tuning speeds included in a speed bar, according to one embodiment. In this figure, the fine tuning speed is calculated using an arithmetic progression method. Note that the legend shown in FIG. 6A is also applied to FIGS. Referring to FIG. 6A, process 300 generates a first set of fine-tuning speeds that are displayed as shown. The generation and / or display of the fine adjustment speed is performed in response to a user request (for example, a fine adjustment request or a zoom request). The current speed 605a (12000 rpm) is part of the original speed bar 215, which exists prior to the start of the fine tuning process and is used during the fine tuning speed generation process. The current speed 605a is surrounded by a first set of fine-tuning speeds 10800, 11100, 11400, and 12600 as calculated in Table 3, respectively. The remaining speed may be made accessible via a scrolling function.

  Referring to FIG. 6B, the operator selected and activated a speed of 11700 rpm. Thus, the current speed 605b is 11700 rpm, the corresponding chatter level measured is 1.2, the number of lobes is 3, while the speed 12000 is the tried speed. Although the display of the fine adjustment speed 11700 has changed from the elliptical shape to the square shape in FIG. 6B, in another embodiment and as described above, the display of the fine adjustment speed 11700 is, for example, the fine adjustment speed as the stable speed. Note that it remains elliptical so that it can be easily distinguished. Since chatter level 1.2 is not within the desired range, the operator proceeds to start at a speed of 11400 rpm. The operator may also choose to select a new speed based on his experience of operating the machine. This activation may be performed in response to a prompt displayed on the interface screen (for example, “Please select another spindle speed”).

  Referring to FIG. 6C, the current speed 605c is 11400 rpm, the corresponding chatter level is 1.3, the number of lobes is 3, while speeds 11700 and 12000 represent previously selected speeds. . Since the current chatter level is not within the desired range, the operator activates another speed of 11100 rpm.

  Referring to FIG. 6D, the current speed 605d is 11100, the corresponding chatter level is 1.6, the number of lobes is 3, while speeds 11400, 11700, and 12000 represent previously selected speeds. ing. Since speed 11700 has the lowest chatter level among the displayed speeds, the operator restarts speed 11700 as shown in FIG. 7A. However, the operator may decide to continue looking for speeds having a chatter level lower than 1.2, for example by selecting other fine-tuning speeds and / or scrolling to other fine-tuning speeds. . The desired range of chatter levels can be set from zero to the chatter threshold level or from zero to the chatter level corresponding to the critical cut depth (line 520 in FIG. 5A).

  The fine tuning process further generates more refined adjustment speeds according to step 330 and displays them on the speed bar as shown in FIGS. The generation and / or display of a more refined fine adjustment speed is performed in response to a user request (eg, a fine adjustment request or a zoom request). These figures illustrate an exemplary interface displayed when a different speed is selected, eg, from a second set of fine-tuning speeds included in a speed bar, according to one embodiment. Note that the legend shown in FIG. 7A is also applied to FIGS. The fine tuning speed is calculated by dividing the speed range in each of the at least one stability lobe into a second predetermined number (eg, 40) portions. For example, when calculating the second set of fine tuning speeds for stable lobes 2 and 3, the fine tuning step for lobe 2 would be (18000-12000) / 40 = 6000/40 = 150 rpm. Similarly, for lobe 3, the fine tuning step will be 75 rpm.

  7B-7E show a display of a second set of fine-tuning speeds with higher resolution than the speeds in FIGS. 6A-6D. Referring to FIG. 7A, the current speed 705a is 11700 rpm, the corresponding lobe number is 3, and the chatter level is 1.2. Although chatter level 1.2 is lower than other speed chatter levels, if desired, to find even lower chatter speeds, or to find the lowest possible chatter level for the displayed fine-tuning speed, Additional fine adjustments are made. While populating the second set of fine-tuning speeds, all other tried speeds may be pushed out to replace the second set of speeds due to display space limitations.

  Referring to FIG. 7B, the current speed 705b is 11700 rpm, the measured chatter level is 1.2, and the tried speeds 11100, 11400, and 12000 are pushed out due to display space limitations. , 11625, 11775 and 11850. To further reduce chatter, the operator tries a speed of 11625 rpm.

  Referring to FIG. 7C, the current speed 705c is 11625 rpm and the measured chatter level is 1.0, while the speed 11700 rpm is the tried speed. Although the display of fine adjustment speed 11625 has changed from an elliptical shape to a square shape in FIG. 7C, in another embodiment and as described above, the display of fine adjustment speed 11625 can be, for example, a fine adjustment speed as a stable speed. Note that it remains elliptical so that it can be easily distinguished. Also, in some embodiments, the display of fine tuning speeds for different fine tuning speed sets may be distinguished by shape, color, and / or other identifying information. The chatter level is lower than previously tried speed, and the operator further decides to try speed 11550 rpm.

  Referring to FIG. 7D, the current speed 705d is 11550 rpm and the measured chatter level is 1.1, while the speed 11625 rpm is the tried speed. Based on the selected speed and the corresponding chatter level history, the operator can easily recognize that the minimum chatter level of 1.0 has been reached at speed 11625, and will restart the speed 11625 rpm as shown in FIG. 7E. Decide. However, the operator may decide to continue looking for speeds having a chatter level lower than 1.0, for example by selecting other fine-tuning speeds and / or scrolling to other fine-tuning speeds. .

  8A-8C illustrate exemplary interface displays when different speeds are selected, eg, from a first set of fine-tuning speeds included in a speed bar, according to one embodiment. The legend shown in FIG. 8A is also applied to FIGS. 8B and 8C. In these figures, the fine tuning speed is calculated using the harmonic sequence method. Referring to FIG. 8A, process 300 generates a first set of fine-tuning speeds that are displayed as shown. The generation and / or display of the fine adjustment speed is performed in response to a user request (for example, a fine adjustment request or a zoom request). The current speed 805a (12000 rpm) is part of the original speed bar 215, which exists prior to the start of the fine tuning process and is used during the fine tuning speed generation process. The current speed 805a is surrounded by a first set of fine-tuning speeds 10588, 10909, 11250, 11613, and 12414 as calculated in Table 4, respectively. The remaining speed may be made accessible via a scrolling function.

  Referring to FIG. 8B, the operator activated by selecting a speed of 11613 rpm. Thus, the current speed 805b is 11613 rpm and the corresponding chatter level measured is 1.2 (note that initially the chatter level is not displayed and is only displayed after the chatter-specific sensor data is collected). The number of lobes is 3, while the speed 12000 is the tried speed. Although the display of fine adjustment speed 11613 has changed from an elliptical shape to a square shape in FIG. 8B, in another embodiment and as described above, the display of fine adjustment speed 11613 can be, for example, a fine adjustment speed as a stable speed. Note that it remains elliptical so that it can be easily distinguished. Since chatter level 1.2 is not within the desired range, the operator proceeds to start at a speed of 11250 rpm. The operator may also choose to select a new speed based on his experience of operating the machine. This activation may be performed in response to a prompt displayed on the interface screen (for example, “Please select another spindle speed”).

  Referring to FIG. 8C, the current speed 805c is 11250 rpm, the corresponding chatter level is 1.4, the lobe number is 3, while speeds 11613 and 12000 represent the previously selected speed. . Since speed 11613 has the lowest chatter level among the displayed speeds, the operator restarts speed 11613 as shown in FIG. 9A. However, the operator may decide to continue looking for speeds having a chatter level lower than 1.2, for example by selecting other fine-tuning speeds and / or scrolling to other fine-tuning speeds. . The desired range of chatter levels can be set from zero to the chatter threshold level or from zero to the chatter level corresponding to the critical cut depth (line 520 in FIG. 5A).

  In one embodiment, the fine tuning process further generates more refined adjustment speeds according to step 330 and displays them on the speed bar as shown in FIGS. Note that the legend shown in FIG. 9A also applies to FIGS. The generation and / or display of a more refined fine adjustment speed is performed in response to a user request (eg, a fine adjustment request or a zoom request). These figures illustrate an exemplary interface displayed when a different speed is selected, for example, from a second set of fine-tuning speeds included in a speed bar, according to one embodiment. The fine tune rate is calculated using a harmonic sequence method in which each lobe for which a further fine tune rate is to be generated is divided into a second predetermined number (eg, 40) portions. In one embodiment, the current speed or another selected speed will be the center of the fine-tuning speed divided by the second predetermined number.

  For example, for the current speed 11613, the number of lobes is 3, and each lobe number increment is 1/40 (= 0.025). The base speed is then divided by 3.175, 3.15, 3.125, (3.1), 3.075, 3.05, etc., which are fine-tuning speeds 11339, 11429, 11520, (11613), 11707, 11803, etc. are given.

  9B-9E show a display of a second set of fine-tuning speeds with higher resolution than the speeds in FIGS. 8A-8C. Referring to FIG. 9A, the current speed 905a is 12000 rpm, the corresponding number of lobes is 3, and the chatter level 1.2 is selected. Although chatter level 1.2 is lower than other speed chatter levels, if desired, to find even lower chatter speeds, or to find the lowest possible chatter level for the displayed fine-tuning speed, Additional fine adjustments are made. While populating the second set of fine-tuning speeds, all other tried speeds may be pushed out of the speed bar to replace the second set of speeds due to display space limitations.

  Referring to FIG. 9B, the current speed 905b is 11613 rpm, the measured chatter level is 1.2, the tried speeds 11250, 11613, and 12000 are omitted, and the speeds 11339, 11429, 11520, 11707, and 11803 are Populated. To further reduce chatter, the operator tries a speed of 11520 rpm.

  Referring to FIG. 9C, the current speed 905c is 11520 rpm and the measured chatter level is 1.0, while the speed 11613 rpm is the tried speed. Although the display of fine adjustment speed 11520 has changed from an elliptical shape to a square shape in FIG. 9C, in another embodiment and as described above, the display of fine adjustment speed 11520 may be, for example, a fine adjustment speed as a stable speed. Note that it remains elliptical so that it can be easily distinguished. Also, in some embodiments, the display of fine tuning speeds for different fine tuning speed sets may be distinguished by shape, color, and / or other identifying information. The chatter level is lower than the previously tried speed and the operator further decides to try speed 11429 rpm.

  Referring to FIG. 9D, the current speed 905d is 11429 rpm and the measured chatter level is 1.1, while the speed 11520 rpm is the tried speed. The operator can easily recognize that the minimum chatter level of 1.0 is reached at speed 11520 and decides to restart speed 11520 rpm as shown in FIG. 9E. However, the operator may decide to continue looking for speeds having a chatter level lower than 1.0, for example by selecting other fine-tuning speeds and / or scrolling to other fine-tuning speeds. .

  While embodiments of the present disclosure have been described using two sets of fine tuning speeds, in other embodiments, only one set of fine tuning speeds, or more than two sets of fine tuning speeds may be utilized. . In addition, the above description mainly describes an embodiment in which a set of fine-tuning speeds is inserted into a speed bar, such as speed bar 215, but the set of fine-tuning speeds is in a separate window (eg, a popup window) Note that it may be displayed.

  In some embodiments, the pop-up window may include only the speed for a single lobe for which the fine tune speed is calculated. These speeds may include only fine-tuning speeds, or may include any speed corresponding to the number of lobes previously calculated or selected.

  In another embodiment, zoom-in and zoom-out functionality may be implemented so that fine-tuning speed begins to appear when zooming in and disappears when zooming out. The zoom in or zoom out configuration focuses on a portion of the speed bar, such as the current speed or any other identified speed (eg, the speed displayed in the center of the speed bar). In this case, the fine adjustment speed may be over a plurality of lobes.

  FIG. 10 shows a block diagram illustrating an example of a hardware configuration of a computer 1000 configured to implement one or more of the various processes described above. For example, in one embodiment, the computer 1000 is configured to control the machine and / or of the chatter gauge element 201, the speed bar 215, the history bar 220, the vibration display element 225, and the speed database and the chatter database. Are configured to provide a CAI 200 that includes one or a combination thereof.

  As shown in FIG. 10, a computer 1000 includes a central processing unit (CPU) 1002, a read only memory (ROM) 1004, and a random access memory (RAM) 1006 that are interconnected to each other via one or more buses 1007. Such a circuit is included. One or more buses 1007 are further connected to an input / output interface 1010. The input / output interface 1010 is connected to an input unit 1012 formed by a keyboard, a mouse, a microphone, a remote controller, a touch screen, or the like. Input / output interface 1010 is also connected to sensors, such as vibration sensors 105 and 106, for example, via input 1012 or communication 1018. The input / output interface 1010 is also formed by an audio interface, a video interface (eg, for outputting displays such as a chatter gauge element 201, a speed bar 215, a history bar 220, and a vibration display element 225), a speaker, and the like. Output unit 1014; recording unit 1016 formed by a hard disk, nonvolatile memory, database, etc .; communication unit 1018 formed by a network interface, modem, USB interface, fire wire interface, etc .; and magnetic disk, optical disk, magneto-optical disk , Connected to a drive 1020 for driving a removable medium 1022 such as a semiconductor memory.

  According to one embodiment, the CPU 1002 loads a program stored in the recording unit 1016 into the RAM 1006 via the input / output interface 1010 and the bus 1007, and then selects one of the CAI 200 elements or them. A program configured to implement the present disclosure, such as providing a combination of functionality, is executed. The recording unit 1016 is, for example, a non-transitory computer readable storage medium. Note that the term “non-transitory” is a limitation of the medium itself (ie, tangible, not a signal) as opposed to limitations on data storage persistence (eg, RAM vs. ROM).

  FIG. 11 is an exemplary system for implementing the CAI 200 of the machine 100 described above. For example, one or a combination of the steps included in the flowcharts shown in FIGS. 2C, 3A, and 3B may be implemented by computer 1000. The interface is displayed on device 1101, which includes touch screen 1102. Device 1101 communicates with computer 1000, which processes information received from device 1101 and transmitted to device 1101 via communication link 1106 that interfaces with communication unit 1018 of computer 1000. Computer 1000 also receives information from vibration sensors 104 and 105 via communication link 1104 that interfaces with communication unit 1018 of computer 1000. Data processed by the computer 1000 is stored in the database 1103, which may be part of the recording unit 1016, or connected via a communication link 1105 that interfaces with the communication unit 1018 of the computer 1000. .

  The various processes described above need not be processed chronologically or simultaneously in the order shown in the flowchart, and the steps can also be performed in parallel, sequentially, or individually (eg, parallelized). Or in an object-oriented manner).

  The program may also be processed by a single computer or by multiple computers on a distributed basis. The program may also be transferred for execution to a single or multiple remote computers.

  Furthermore, in this specification, the term “system” means a collection of a plurality of components (devices, modules (parts), displays, etc.). All components may or may not be housed in a single housing. Therefore, a plurality of components housed in separate housings and connected via a network are considered as a network, and a single component formed by a plurality of modules housed in a single housing Is also considered a system.

  In addition, the technology is not limited to the above-described embodiments when embodied, and various modifications, changes, and alternatives may be made in the technology as long as they are within the spirit and scope thereof. It should be understood that it is good. For example, this technology may be built for cloud computing where a single function is shared between multiple devices over a network and processed in a coordinated manner.

The above disclosure also encompasses the embodiments described below.
(1) A system including a circuit, wherein the circuit determines a predetermined speed of the machine, identifies a stability lobe based on the predetermined speed of the machine, and corresponds to the identified stability lobe. A system configured to select a first set of fine tune speeds from a range of speeds and to operate the machine at one or more of the first set of fine tune speeds.

  (2) The system of feature (1), wherein the circuit is configured to determine a predetermined speed of the machine based on the current operating speed of the machine.

  (3) The system of feature (1) or (2), wherein the circuit is configured to identify a stability lobe corresponding to a predetermined speed of the machine.

  (4) The circuit is configured to determine a lobe width of the identified stable lobe, the lobe width corresponds to a range of machine speeds, and the circuit further determines the determined lobe width to the first lobe width. A first interval is determined by dividing by a predetermined number and is configured to select a first set of fine tuning speeds from a range of machine speeds, each of the first set of fine tuning speeds. Is a system according to any one of features (1) to (3), separated according to a first spacing.

  (5) The circuit is configured to determine a base speed of the machine and select a first set of fine-tuning speeds from a range of machine speeds based on the base speed and the number of lobes of the identified stable lobes. The system according to any one of features (1) to (4).

  (6) The circuit calculates the base speed / (number of identified stable lobes lobe + m / first predetermined number), where m is a number of consecutive M integers corresponding to each fine-tuning speed. The feature (5) is configured to select each of the M fine-tuning speeds included in the first set of fine-tuning speeds from a range of machine speeds using the equation The system described in.

  (7) The circuit further determines a second interval by dividing the determined lobe width by a second predetermined number and selects a second set of fine tuning speeds from a range of machine speeds. Each of the second set of fine tuning speeds is separated based on the second spacing, and the circuit further includes a machine at one or more of the second set of fine tuning speeds. The system of feature (4), wherein the system is configured to operate.

  (8) The circuit further includes base speed / (number of identified stability lobes + n / second predetermined number), where n is a number of consecutive N integers corresponding to each fine-tuning speed. The feature (6) is configured to select each of the N fine tuning speeds included in the second set of fine tuning speeds from the range of machine speeds using the formula ) System.

  (9) The circuit measures the chatter level when the machine operates at the first set of fine tuning speeds, and which of the first set of fine tuning speeds is the lowest of the measured chatter levels. The system according to any one of features (1) to (8), wherein the system is configured to automatically determine whether it corresponds to the one.

  (10) A method for selecting a fine-tuning speed for reducing machine chatter, the method comprising: determining a predetermined speed of the machine by means of a circuit of the system; Identifying a stability lobe based on the identified speed, selecting a first set of fine tuning speeds from a range of machine speeds corresponding to the identified stability lobe by a circuit, and a first set of fine adjustments. Operating the machine at one or more of the adjustment speeds.

  (11) The method of feature (10), wherein the determining step includes the step of determining a predetermined speed of the machine based on the current operating speed of the machine.

  (12) The method of feature (10) or (11), wherein identifying the stability lobe includes identifying a stability lobe corresponding to a predetermined speed of the machine.

  (13) selecting comprises determining a lobe width of the identified stable lobe, the lobe width corresponding to a range of machine speeds, and the selecting step further comprises: determining the determined lobe width to the first A first interval by dividing by a predetermined number of and a step of selecting a first set of fine tuning speeds from a range of machine speeds, wherein the first set of fine tuning speeds The method of any one of features (10)-(12), each separated based on a first spacing.

  (14) selecting comprises determining a base speed of the machine and selecting a first set of fine-tuning speeds from a range of machine speeds based on the base speed and the number of lobes of the identified stability lobes. The method according to any one of features (10) to (13), comprising:

  (15) The step of selecting is: base speed / (number of identified stable lobes lobe + m / first predetermined number) (m is a sequence of M integers corresponding to each fine-tuning speed A feature (14) comprising the step of selecting each of the M fine tuning speeds included in the first set of fine tuning speeds from a range of machine speeds using a formula of The method described.

  (16) The method further includes determining a second interval by dividing the determined lobe width by a second predetermined number and selecting a second set of fine tuning speeds from a range of machine speeds. Each of the second set of fine tuning speeds is separated based on the second interval, and the method further includes the machine at one or more of the second set of fine tuning speeds. The method of feature (13), comprising the step of operating.

  (17) The method further includes base speed / (number of identified stable lobes lobe + n / second predetermined number), where n is a sequence of N integers corresponding to each fine-tuning speed. And selecting each of the N fine-tuning speeds included in the second set of fine-tuning speeds from the range of machine speeds using the equation the method of.

  (17) The method further includes a base speed / (number of identified stable lobes lobe number + n / second predetermined number), where n is a consecutive number corresponding to each fine-tuning speed. Selecting each of the N fine tuning speeds included in the second set of fine tuning speeds from a range of machine speeds using.

  (18) The method includes the step of measuring the chatter level when the machine operates at the first set of fine tuning speeds, and which of the first set of fine tuning speeds is among the measured chatter levels. And automatically determining whether it corresponds to the lowest one of the features (10) to (17).

  (19) A non-transitory computer-readable medium that stores a program that, when executed by a computer, causes the computer to perform a method of selecting a fine-tuning speed to reduce machine chatter. Determining a predetermined speed of the machine, identifying a stability lobe based on the machine's predetermined speed, and a first set of fine adjustments from a range of machine speeds corresponding to the identified stability lobe. A non-transitory computer readable medium comprising: selecting a speed; and operating the machine at one or more of a first set of fine-tuning speeds.

  (20) A non-transitory computer-readable medium storing a program that, when executed by a computer, causes the computer to perform the method according to any one of features (11) to (18).

  100 machine, 101 spindle housing, 102 cutting tool, 103 workpiece, 104, 105 vibration sensor, 200 CAI, 201 gauge element, 203 circular dial, 205 threshold mark, 207 level numerical display, 209 level indicator, 211 fixed gauge Mark, 215 speed bar, 215A fine adjustment speed screen, 220 history bar, 225 vibration display element, 502a peak, 520 line, 1000 computer, 1101 device, 1102 touch screen, 1103 database, 1104, 1105, 1106 communication link.

Claims (19)

A system including a circuit,
The circuit is
Determine the predetermined speed of the machine,
Identifying a stability lobe based on the predetermined speed of the machine;
Selecting a first set of fine tuning speeds from a range of machine speeds corresponding to the identified stability lobes;
A system configured to operate the machine at one or more of the first set of fine tuning speeds.   The system of claim 1, wherein the circuit is configured to determine the predetermined speed of the machine based on a current operating speed of the machine.   The system of claim 1, wherein the circuit is configured to identify the stability lobe corresponding to the predetermined speed of the machine. The circuit is configured to determine a lobe width of the identified stability lobe;
The lobe width corresponds to the machine speed range;
The circuit further includes:
Determining a first interval by dividing the determined lobe width by a first predetermined number;
Configured to select the first set of fine tuning speeds from the range of machine speeds;
The system of claim 1, wherein each of the first set of fine tuning speeds is separated based on the first spacing. The circuit is
Determine the base speed of the machine,
The system of claim 1, configured to select the first set of fine-tuning speeds from the range of machine speeds based on the base speed and the number of lobes of the identified stability lobes.   The circuit is based on base speed / (number of identified stability lobes + m / first predetermined number), where m is one of M consecutive integers corresponding to each fine-tuning speed. 6. Each of the M fine tuning speeds included in the first set of fine tuning speeds is selected from the range of the machine speeds using the formula The described system. The circuit further includes:
Determining a second interval by dividing the determined lobe width by a second predetermined number;
Configured to select a second set of fine tuning speeds from the range of machine speeds;
Each of the second set of fine tuning speeds is separated based on the second spacing;
The system of claim 4, wherein the circuit is further configured to operate the machine at one or more of the second set of fine tuning speeds.   The circuit further includes base speed / (number of identified stability lobes lobe number + n / second predetermined number), where n is one of N consecutive integers corresponding to each fine-tuning speed. 8 is configured to select each of N fine tuning speeds included in the second set of fine tuning speeds from the range of the machine speeds. The system described in. The circuit is
If the machine operates at the first set of fine tuning speeds, measure the chatter level;
2. The apparatus of claim 1, configured to automatically determine which one of the first set of fine tuning speeds corresponds to the lowest of the measured chatter levels. system. A fine tuning speed selection method for reducing machine chatter,
Determining by a circuit of the system a predetermined speed of the machine;
Identifying a stability lobe by the circuit based on the predetermined speed of the machine;
Selecting, by the circuit, a first set of fine tuning speeds from a range of machine speeds corresponding to the identified stability lobes;
Operating the machine at one or more of the first set of fine adjustment speeds.   The method for selecting a fine-tuning speed according to claim 10, wherein the determining includes determining the predetermined speed of the machine based on a current operating speed of the machine.   The method of claim 10, wherein identifying the stability lobe comprises identifying the stability lobe corresponding to the predetermined speed of the machine. Said selecting comprises determining a lobe width of said identified stable lobe, said lobe width corresponding to said machine speed range;
The step of selecting further comprises:
Determining a first interval by dividing the determined lobe width by a first predetermined number;
Selecting the first set of fine tuning speeds from the range of machine speeds;
The method of selecting a fine adjustment speed according to claim 10, wherein each of the first set of fine adjustment speeds is separated based on the first interval. The step of selecting includes
Determining a base speed of the machine;
Selecting the first set of fine tuning speeds from the range of machine speeds based on the base speed and the number of lobes of the identified stability lobes. Selection method.   The step of selecting comprises: base speed / (number of identified stable lobes lobe + m / first predetermined number), where m is a number of consecutive M integers corresponding to each fine-tuning speed. 15. The method of claim 14, comprising selecting each of M fine tuning speeds included in the first set of fine tuning speeds from the range of machine speeds using the equation How to select the fine adjustment speed. The method for selecting the fine adjustment speed further includes:
Determining a second interval by dividing the determined lobe width by a second predetermined number;
Selecting a second set of fine tuning speeds from the range of machine speeds;
Each of the second set of fine tuning speeds is separated based on the second spacing;
14. The fine tuning speed selection method of claim 13, wherein the fine tuning speed selection method further comprises operating the machine at one or more of the second set of fine tuning speeds.   The fine-tuning speed selection method further includes base speed / (number of identified stable lobes lobe + n / second predetermined number) (where n is a number of consecutive N corresponding to the respective fine-tuning speeds. Selecting each of the N fine-tuning speeds included in the second set of fine-tuning speeds from the range of machine speeds using an expression of one of an integer). Item 17. The fine adjustment speed selection method according to Item 16. The method for selecting the fine adjustment speed is as follows.
Measuring the chatter level when the machine operates at the first set of fine-tuning speeds;
11. The fine tuning of claim 10, comprising automatically determining which of the first set of fine tuning speeds corresponds to the lowest of the measured chatter levels. Speed selection method. A non-transitory computer readable medium storing a program that, when executed by a computer, causes the computer to perform a fine tuning speed selection method for reducing machine chatter,
The method for selecting the fine adjustment speed is as follows.
Determining a predetermined speed of the machine;
Identifying a stability lobe based on the predetermined speed of the machine;
Selecting a first set of fine tuning speeds from a range of machine speeds corresponding to the identified stability lobes;
Operating the machine at one or more of the first set of fine-tuning speeds.

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